Anxiety disorders are among the most frequently occurring psychiatric conditions in the population, and are associated with serious personal and societal costs. While anxiety has independently been associated with significant sleep disruption and dysfunctional emotional brain regulation, the interaction amongst these three factors is poorly understood. Characterizing this interactive association may offer the potential not only to gain a deeper understanding of the pathophysiological mechanisms underlying anxiety, but also aid in the development of preventative strategies and effective treatments for the amelioration of anxiety. These proposed experiments combine functional MRI (fMRI), high-density sleep EEG recordings and behavioural assessments to test the hypotheses that high anxiety status (a) predisposes individuals to the deleterious effects of sleep deprivation and (b) subsequently negates the restorative benefit of recovery sleep on emotional brain reactivity, following deprivation. Considering the continued erosion of sleep time across society and the high prevalence of anxiety disorders, understanding the causal associations between anxiety, sleep impairment, and emotional brain reactivity has considerable therapeutic, clinical and public health ramifications. PUBLIC HEALTH RELEVANCE: Combining brain imaging (fMRI) and high-density EEG measures of sleep, this proposal aims to characterize how anxiety, and the abnormalities associated with anxiety, predispose individuals to the deleterious effects of sleep deprivation, and subsequently prevents the restorative benefit of recovery sleep, on emotional brain reactivity. Considering the continued erosion of sleep time across society and the high prevalence of anxiety disorders, understanding the causal associations between anxiety, sleep impairment, and emotional brain reactivity has considerable therapeutic as well as clinical and public health ramifications.